NEW YORK -- The black box data recorder was recovered from a commuter train that derailed as it hurtled around a sharp curve in the Bronx, killing four people and injuring dozens of others, investigators said late Sunday.
The device will be analyzed to determine what caused all seven cars of the Metro-North Commuter Railroad to jump the tracks near the historic Spuyten Duyvil station in the Bronx at around 7:22 a.m. ET on Sunday.
The train's engineer told first responders when they arrived at the scene that he had hit the brakes as the train approached the turn, sources told NBC News on Sunday afternoon. He was a "respected veteran" with 20 years of Metro-North experience who suffered minor injuries, the sources said.
NBC New York: Speed eyed as a factor in deadly Metro-North crash
Passenger Dennis O'Neil told NBC New York he believed the train was going too fast. "It was coming towards Spuyten Duyvil and you could feel it starting to lean and it was like, 'hey, what's going on,'" he said. "And then it hit the curb real hard and flopped over and slid down the hill. A couple people were hurt very badly right in front of me."
New York Gov. Andrew Cuomo said the scene "looked like a child’s train set, just strewn about," speaking to TODAY on Monday.
He added that investigators had not told him how long it would take to analyze the black box, but he believes the cause of the crash would turn out to be speed-related.
"This was a tricky turn on the system, but it is a turn that’s been here for decades," he said.
MTA spokeswoman Marjorie Anders told NBC New York that the curve where the train derailed is in a slow-speed area, where the limit is 30 mph. The area just before the curve is a 70 mph limit, according to Anders. The black box should be able to tell how fast the train was traveling, she said.
The data recorder should also show whether its brakes did, in fact, fail.
Officials said at least 63 people were injured as passengers were tossed around like rag dolls. Many of them use Metro-North to get to work and would have to overcome psychological trauma to use the railway again, an emergency room doctor said.
"A 14-year-old who was traveling with his father, who was also injured, takes Metro-North to go to school in the Bronx," said Dr. David Listman of St. Barnabas Hospital. "From his perspective, how he is going to get back on a Metro-North train to come to school every day?"
The Metropolitan Transportation Authority identified the four passengers who were killed as Jim Lovell, 58, of Cold Spring, N.Y.; James Ferrari, 59, of Montrose, N.Y.; Donna Smith, 54, of Newburgh, N.Y.; and Ahn Kisook, 35, of Queens.
Lovell, a father of four, was an audio technician who frequently worked on TODAY and other NBC programs.
Fire officials said that as many as 11 of the injured were critical and that six were in serious condition.
Meanwhile, Cuomo warned that "people who use these lines should plan on a long commute" on Monday.
A portion of a Metro-North Railroad line between the Bronx and part of Westchester County could be closed for a week or more.
Service was suspended on the railroad's Hudson line, which serves 26,000 on an average weekday, between the village of Tarrytown and Grand Central Terminal, according to the MTA.
Metro-North said Sunday's 5:54 a.m. diesel train from Poughkeepsie derailed just feet from the water near the station. It was due at Grand Central Station at 7:43 a.m.
The train was half full, with about 150 passengers, rail officials said. The locomotive was on the north end of the train, pushing the cars southward.
"On a workday, fully occupied, it would have been a tremendous disaster," Fire Commissioner Salvatore Joseph Cassano told reporters at the scene.
One of the victims was found in the first car, one was found outside that car, another was found near the second and third cars, and the fourth was found outside the fourth car.
Earl Weener, a member of the National Transportation Safety Board, said the condition of the tracks and the cars will be the focus of the NTSB probe, along with the speed the train was traveling. The investigation is expected to take a week to 10 days.
Sherelle Coore, a 19-year-old college student from the Bronx who was aboard the train, told her cousin from her hospital bed that she felt a "jerking" movement and then everything started happening very quickly.
"She hit the side of her head," Coore's cousin, Lisa Delgado, told NBC New York. "She saw the woman in front of her go out the other window. Her glass broke, and she hung on to the side rails like a monkey while the train was flipping and the rocks were coming in."
Sherry Nemmers, who lives near the scene, told NBC News that she heard a sound "that was a little too familiar for me." She'd heard it before this summer, when a CSX freight train hauling trash on the same line derailed near the same area of the Bronx.
"I heard this thud — this dull thud. It sort of sent chills up me because it was a sound that I heard in July," Nemmers said. "I was afraid that it was going to be a train, and it was."
No one was injured in July, but questions were raised about the safety of the track's design and its notoriously sharp turn right before the station. Cuomo noted that the two accidents happened at about the same location but said, "There has to be another factor. ... It can't just be the curve."
Weener said the agency would examine whether Sunday's incident could be related, but he said, "At this point in time, we have no indication it was a factor."
At St. Barnabas Hospital in the Bronx, where a dozen victims were taken, officials said one was in critical condition on Monday morning with a spinal cord injury. At New York Presbyterian, two were in critical condition.
Sources said five off-duty New York officers were among the injured, all with relatively minor injuries and reported to be stable.
Metro-North Hudson line service was suspended in both directions. Amtrak service between New York and Albany reopened in midafternoon with delays.
President Barack Obama was informed of the crash by the Department of Homeland Security, a White House official said. "His thoughts and prayers go out to the friends and families who lost a loved one and everyone affected by this incident," the official said.
MTA officials said JFK High School in the Bronx has been established as a meeting area for passengers and their loved ones, and 718-817-7444 is the contact number for those seeking the status of relatives who may have been aboard the train.
NBC News' Hasani Gittens, M. Alex Johnson, Alexander Smith, Jason Cumming, Elisha Fieldstadt, Katy Tur, Tom Winter, Kristen Dahlgren and Christopher E. Nelson contributed to this report.
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